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61.
62.
The temperature dependences of some selected infrared bands of poly(vinylchloride) in the vicinity of the glass transition were examined. The intensities of 1333 and 1427 cm?1 bands changed discontinuouly at Tg; on the other hand, 2920 cm?1 did not show any significant changes at this temperature. From these results, the nature of the temperature dependence of infrared intensity of the polymer was discussed. The procedure introduced in this work offers a rapid method for the determination of the Tg as compared with the conventional infrared methods.  相似文献   
63.
Irinotecan hydrochloride (CPT-11) is a new derivative of camptothecin which inhibits topoisomerase I. Phase II studies have demonstrated that CPT-11 is active against a broad spectrum of neoplasms including intractable non-Hodgkin's lymphoma. An early phase II study in lymphoma suggested that a schedule of daily infusions of 40 mg/m2/day for three or five consecutive days is more effective than a single infusion of 200 mg/m2 every three to four weeks. Carboplatin is also an active agent against lymphoma, and preclinical studies have shown that CPT-11 and its active metabolite have a synergistic effect with platinum compounds. To evaluate the maximal tolerated dose (MTD) and the therapeutic efficacy of CPT-11 in combination with carboplatin in relapsed or refractory non-Hodgkin's lymphoma, we conducted a combination phase I/II study. The starting dose of CPT-11 was 20 mg/m2/day (days 1 through 3 and 8 through 10), and dose escalations of 5 mg/m2/day increments were planned, with a fixed dose of carboplatin (300 mg/m2, day 1). Six of the eight patients receiving both agents at the starting dose level developed critical toxicities such as grade 4 hematologic (neutropenia 6/8, thrombocytopenia 1/8) and grade 3 non-hematologic toxicities (diarrhea 2/8, transaminase elevation 1/8). Further dose escalation of CPT-11 was halted, and the starting doses were judged to be the MTDs. The response rate (25%, 2/8) to the combination of the MTDs was not superior to that of CPT-11 alone in a previous phase II study (38%, 26/69), and the MTD of CPT-11 in combination with carboplatin was less than half the single-agent dose. We conclude that carboplatin is not recommendable for combination with CPT-11 in lymphoma patients. Other suitable agents for such a combination should be sought.  相似文献   
64.
Pertussis vaccinations are administered worldwide under various conditions and schedules with diphtheria-tetanus-pertussis (DTP). In Japan, a general vaccination with three primary doses of diphtheria-tetanus-acellular pertussis (DTaP) at 4-week intervals and one booster dose 12 months after the primary series have been used since 1981. Decreasing the number of doses of the vaccination would lessen the physical and economic costs. To compare the immunological response to two versus three primary doses, we assessed antibody and cellular immune responses in health children. The anti-filamentous hemagglutinin (anti-FHA) and anti-pertussis toxin (anti-PT) antibody responses to two primary doses of DTaP before a booster were significantly lower than the responses to three primary doses. Although these antibody levels were low in children who received two primary doses, the FHA-induced DNA synthesis was equal to that of the children who received three doses. The anti-FHA and anti-PT antibody levels 4 weeks after the booster following two doses were similar to the levels following three doses, and high antibody titers were maintained over a long period. In areas where contact with bacteria is expected, two primary doses of DTaP may be adequate to induce the necessary level of immunological responses.  相似文献   
65.
PURPOSE: To report a method to evaluate leukocyte dynamics in the choroidal circulation with indocyanine green (ICG) angiography. METHODS: Nonpigmented and pigmented rats were administered ICG solution intravenously. The fundus image was obtained with a scanning laser ophthalmoscope and recorded on magnetic tapes at a video rate (30 frames/second). The images were analyzed with a personal computer-based image analysis system. RESULTS: On ICG angiography, hyperfluorescent dots were seen moving along the choroidal vessels and in the retinal vessels several minutes after injection. These fluorescent dots were thought to be circulating leukocytes stained with ICG. The micrographs of blood smears after ICG injection showed intense fluorescence of leukocytes. Computer-assisted image analysis allowed tracing of these fluorescent dots using a frame-by frame method. CONCLUSIONS: Results of this study indicated that ICG can be used for vital staining of leukocytes and that it is possible to evaluate leukocyte movement in the choroidal circulation in vivo in rats.  相似文献   
66.
We measured low-temperature heat capacities of two-dimensional Fermi liquid (2D FL) formed on Hectorite down to 15mK. At a coverage where mean atomic distance is comparable to that of bulk 3 He liquid, we found that the temperature dependence deviates considerably from the expected linearity. To account for the deviation we carried through integrals including RPA spin susceptibility for the Stoner-Hubbard(SH) or the Landau's Fermi liquid (LFL) models over the effectively entire, energy-momentum space without imposing the paramagnon approximation or the like. We found numerically that the spin fluctuation develops a T 2 correction at T<T* which, at T>T*, is taken over by a Tlog T term where T* is some hundredths of T F . With these corrections we are able to interprete the data and have determined the parameters for each model consistently at the densities observed.  相似文献   
67.
Vertical-to-surface transmission electrophotonic devices with a vertical-cavity are described. The individually accessed 12×4 arrays are characterized and demonstrated to have uniform room-temperature continuous-wave operating characteristics for a threshold current of ~2.8±0.15 mA and a slope efficiency of ~0.18±0.012 W/A with a single transverse mode. Both low threshold and high efficiency with 5% and 7% deviation, respectively, are achieved simultaneously. These devices can be used to constructing two-dimensional massively parallel optical interconnections  相似文献   
68.
The cyclic voltammograms of ferrous complexes of 5-substituted 1,10-phenanthroline were obtained. The anodic and the cathodic peak potentials shifted toward positive side by substituting electron-withdrawing group for 5-hydrogen in 1,10-phenanthroline. This result was interpreted by that the probability of the transition of electron from d orbital to the empty MO of the ligand was increased by the introduction of electron-withdrawing group, and hence the oxidation of the ferrous complex became more difficult. The oxidized substances of ferrous complex containing this functional group were labile and decomposed chemically.  相似文献   
69.
An automatic system for rapid determinations of the activities of FeO in metallurgical slags has been developed. With this facility, one datum is obtainable within 5 minutes. The facility was applied for the activity measurements in the system CaO + SiO2 + FeO, while activity data obtained were consistent with those deduced from the phase diagram.  相似文献   
70.
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